Hand grenade



W. KULA HAND GRENADE Sept. 19, 1944.

2 Sheets- Sheet 1 Filed Aug. 12 1941 J a? a Patented Sept. 19, 1944 HAND GRENADE Wiktor Kula, London, England Application August 12, 1941, Serial No. 406,551

In Great Britain August 8, 1940 2 Claims;

The hand grenades at present in use are fitted with safety devices for preventing them from exploding until a safety pin is withdrawn. The known form of safety device does not however obviate the risk of injury in the event of the grenade being dropped after withdrawal of the safety pin and before it is thrown at the target. This may easily happen if the user should be wounded when about to throw the grenade.

The object of the present invention is to provide a hand grenade having a safety device which operates to maintain the percussion mechanism inoperative until after the grenade has been thrown and has travelled for a certain distance.

According to the invention the grenade is fitted with a safety latch, for preventing operation of the percussion mechanism, said latch being coupled to a member arranged to be displaced relatively to the body of the grenade due to the resistance of the air, when the grenade is thrown, thereby withdrawing the safety latch.

One form of grenade according to the invention is illustrated by way of example in the accompanying drawings, whereof Fig. 1 is a section through the longitudinal axis of the grenade, and Fig. 2 a fragmentary sectional view depicting the relative disposition of the movable parts when the safety bolt is partially withdrawn.

It will be seen from such drawings that the shell a of the grenade has built into it three tubes 0, d and e. The tube is filled with a charge t of high explosive material I), with which the body of the grenade is likewise filled. The percussion mechanism is located in the tube d and comprises a weight 2 supported on a sliding conical member I carrying at its lower end a firing pin g, above which is disposed a collar p which rests on a safety bolt :1, k. The portion 7c of the safety bolt is slidably mounted in the tube e and the portion 7' normally serves to intercept the collar p and prevent the firing pin g from coming into contact with the percussion cap h, said portion 7' being supported in the position illustrated in Fig. 1 by the projecting lip or lug (P. The weight of the parts 2 and f is balanced by a spring I, the lower end of which abuts against a member 12 which serves as a guide for the bolt 7', k, and it will be understood that it requires a sufficiently sharp impact, such for example as occurs when the grenade falls on being thrown, to enable the inertia of the weight 2' to overcome the pressure of the spring Z to operate the percussion mechanism.

The safety bolt is held in the safety position by a handle m through the agency of two springs n, o. The'lower end of the spring 0 is secured to the handle m whileits upper end a: bears freely against the end of the portion is of the safety bolt, 7', k. The spring n bears against the side of the shell a at v and its upper extremity passes through the portion of the bolt k to bear against the side of the shell a at v 7 The handle m is kept in place by a tongue 'q on the outer face of the shell a, beneath which tongue q one end of the said handle rests, and by a pin r securing the handle to a lug s on the grenade. The pin r passes through aligned holes in lugs e on the handle which are disposed one at each side of the lug s. The handle is attached to one end of the bolt lc by a string u, in such manner that the withdrawal of they bolt 7', k: is effected by the outward displacement of the handle m in relation to the grenade through the medium of said string u. The spring 0 is stronger than the spring n, so that when the handle is secured in the closed position illustrated in Fig. 1, the tendency of the spring n to retract the bolt is overcome and the bolt is held in the safety position.

When it is desired to use the grenade, the pin r is withdrawn. This operation does not of itself render the grenade liable to explode on impact, because the safety bolt 7', is still acts to prevent operation of the percussion mechanism. When however the grenade is thrown, the handle m is forced away from the body of the grenade first by the springs n, o, and secondly by the resistance of the air, thereby withdrawing the safety bolt through the agency of the string u. Only when the grenade has travelled a sufficient distance to withdraw the end 7' of the safety bolt 7'. is from beneath the collar p can an explosion occur, so that all danger of premature explosion is removed.

Assuming, however, that the grenade has travelled a sufiicient distance to complete the withdrawal of the safety bolt, it will explode on impact however it strikes the target. Thus, if the bottom of the grenade should receive the impact, the weight 2' will push the firing pin g down through a hole c of the tube 0 and into contact with the cap h. If the top of the grenade receives the impact, the inertia of the charge 1. will cause it and the cap h to travel forwards until the latter meets the firing pin 9. If the grenade should fall upon its side, the inertia of the weight 2' acting laterally against the conical upper surface of the member f will force the latter downwards to detonate the charge.

The member I is formed with holes as shown so as to prevent air from being trapped beneath it and hindering its movement into the firing position.

The preferred embodiment of the invention shown in the drawings is particularly advantageous in that the premature detonation of the charge is eifectively prevented by the use of the two-part safety bolt k. It willbe seen on reference to Fig. 2 that the sections of the bolt are pivotally connected aty' and the arrangement is such that the bolt requires to becompletely withdrawn through the agency of the string a and springs n, o to enable the weight 2' to operate the firing pin g. Should the bolt be only partly withdrawn, as depicted in Fig. 2, an impact caused, e. g. by falling on the ground, or a sudden jerk, would cause the portion j to'pivot out of alignment under the weight i, so as to abut at 70 against the end of the tube e and thereby prevent further outward movement of the bolt, thus preventing the firing pin 9 from coming into operative contact with the cap it.

If desired, the weight i may be made of a material which, on the explosion of the grenade, either becomes ignited or molten, or disintegrates into small fragments. a

The tube e in which the safety ,bolt is mounted also serves to prevent portions of the charge b from falling out of the shell 11' when the bolt is withdrawn.

What I claim as my invention and desire to upon the grenade with capability of relative outward displacement therefrom when the grenade is thrown, a connection between said bolt and said displaceable member, and a detent fixed with respect to the housing, said bolt comprising two axially aligned parts pivoted end to end and the bolt and precluding the effective operation of the percussion mechanism. V

2. A hand grenade comprising in combination with a housing and percussion mechanism a retractile' safety bolt, a member mounted exteriorly' upon thev grenade with capability of relative outward displacement therefrom when the grenade is thrown, a spring compressed between the safety bolt and said displaceable member, a connection between said boltcand said, displaceable member, a second spring weaker than the first spring compressed between the bolt and the body of the grenade, and a detent fixed with respect to the housing, said bolt comprising two axially aligned and pivotally connected parts so arranged that a partial withdrawal 'of the bolt accompanied by an impact upon or jerk of the grenade, such as might tend to operate the percussion mechanism, operates to cause one part of the boltto pivot out of its normal alignmentwith the other part thereof and so engage said detent, thereby preventing further'withdrawal of the bolt and prey cluding the efiective operation of the percussion mechanism.

: WIKTOR KULA. 

